using System;
using System.Runtime.InteropServices; 
using NagCFunctionsAPI;

public class NagG02Functions
{
  
  public static void nag_regsn_mult_linear(int mean_int, int n, double [,] x, int m,
                                           int [] sx, int ip, double [] y, double [] wt,
                                           ref double rss, ref double df, double [] b,
                                           double [] se, double [] cov, double [] res,
                                           double [] h, double [,] q, ref int svd,
                                           ref int rank, double [] p, double tol,
                                           double [] com_ar, ref int fail_int)
    {
    
      NagError fail = new NagError();
      fail.char_array = new char [512];
      
      int tdx = m;
      int tdq = ip + 1;
      NagFunctions.g02dac(mean_int, n, x, tdx, m, sx, ip, y, wt, ref rss,
                          ref df, b, se, cov, res,
                          h, q, tdq, ref svd, ref rank,
                          p, tol, com_ar, ref fail);
        
      fail_int = fail.code;
      if (fail.code != 0)
        Console.WriteLine(fail.char_array);
    }
  public static void Main()
    {
      int mean_int = 1358;
      int n = 12;
      int m = 4; 
      int fail_int=0;
      double [,] x = new double [,] {
        { 1.0, 0.0, 0.0, 0.0 },
        { 0.0, 0.0, 0.0, 1.0 },
        { 0.0, 1.0, 0.0, 0.0 },
        { 0.0, 0.0, 1.0, 0.0 },
        { 0.0, 0.0, 0.0, 1.0 },
        { 0.0, 1.0, 0.0, 0.0 },
        { 0.0, 0.0, 0.0, 1.0 },
        { 1.0, 0.0, 0.0, 0.0 },
        { 0.0, 0.0, 1.0, 0.0 },
        { 1.0, 0.0, 0.0, 0.0 },
        { 0.0, 0.0, 1.0, 0.0 },
        { 0.0, 1.0, 0.0, 0.0 }
      };
     
      double [] y = new double[] { 33.63, 39.62, 38.18, 41.46, 38.02,
                                   35.83, 35.99, 36.58, 42.92, 37.80,
                                   40.43, 37.89};
      int [] sx = new int[m];
      for (int i = 0; i<m; i++)
        sx[i] = 1;
     
      int ip = mean_int == 1358 ? ip = m+1 : m;
      double [] b = new double [ip];
      double [] se = new double [ip];
      double [] cov = new double [ip*(ip+1)/2];
      double [] res = new double [n];
      double [] h = new double[n];
      double [,] q = new double[n, ip+1];
      double [] p = new double [2*ip+ip*ip];
      double [] com_ar = new double [5*(ip-1)+ip*ip];
      
      int svd=0;
      int rank=0;
      
      double [] wt = new double[n];
      for (int i=0; i<n; i++)
        wt[i] = 1.0;
          
      double rss=0.0, df=0.0, tol=0.00001;
          
      nag_regsn_mult_linear(mean_int, n, x, m, sx, ip, y,
                            wt, ref rss, ref df, b, se, cov, res,
                            h, q,  ref svd, ref rank, p, tol, com_ar, ref fail_int);
      if (svd == 1)
        Console.WriteLine("Model not of full rank, rank = {0}", rank);
      Console.WriteLine("Residual sum of squares = {0,12:e4}", rss);
      Console.WriteLine("Degrees of freedom = {0, 3:f1}", df);
      Console.WriteLine();
      Console.WriteLine("Variable    Parameter estimate   Standard error");
      for (int j=0; j<ip; j++)
        Console.WriteLine("{0, 6:d} {1, 20:e4} {2, 20:e4}", j+1, b[j], se[j]);
      Console.WriteLine();
      Console.WriteLine("    Obs         Residuals              h");
      for (int i=0; i<n; i++)
        Console.WriteLine("{0, 6:d} {1, 20:e4} {2, 20:e4}", i+1, res[i], h[i]);
    }
}